COLUMBUS, Ohio (CNN) -- With oil prices nearing last year's record highs, President Bush renewed his call for Congress to authorize oil exploration in Alaska's largest wildlife refuge as part of a broader energy bill.

In a speech Tuesday in Ohio, Bush urged lawmakers to pass the energy bill that has stalled in Congress since the beginning of his first term, saying it would wean the United States away from overseas sources of crude.

"We have had four years of debate about a national energy bill. Now's the time to get the job done," he said.

Bush spoke after a visit to the Battelle Memorial Institute, a non-profit research corporation that is working on developing hydrogen fuel cells. He said he said reducing U.S. dependence on oil imports will be good for the economy and for national security.

But the sticking point for his last energy bill was a provision that would have opened a portion of the Arctic National Wildlife Refuge in Alaska to oil exploration.

"Developing small section of ANWR would not only create thousands of new jobs, but it would eventually reduce our dependence on foreign oil by up to 1 million barrels of oil a day," Bush said.

Advocates like the American Petroleum Institute, the oil industry's trade association, say the refuge sits atop enough oil to replace U.S. imports from Saudi Arabia for two decades.

Environmental groups like the Sierra Club say that figure is wildly overstated, arguing that any oil reserves beneath the refuge's coastal plain would last less than a year -- while opening the refuge to oil exploration would inflict irreparable damage to the vast wilderness area.

But Bush said oil exploration can be limited to a 2,000-acre site -- "the size of the Columbus airport" -- and could be done "with almost no impact on land or local wildlife."

He said drilling in ANWR should be part of an overall energy bill that would promote conservation, increase domestic energy production and modernize infrastructure such as power grids and pipelines.

Bush's proposed budget for 2006 would cut funding for research into energy conservation by 2.5 percent, from $868 million to $847 million, though some efforts -- like research into hydrogen-powered vehicles and fuel cell technology -- would see increases.

The overall request for "energy security" -- which includes funding for power grids and pipelines, nuclear, fossil fuel and hydroelectric research -- is down 2.7 percent from the 2005 budget, from $2.8 billion to $2.7 billion.

The president spoke as crude oil prices hit record highs in London and moved above $55 a barrel in New York, coming within two cents of the $55.67 record set in October before closing at $54.77.

The rising prices have prompted new calls by several senators for Bush to release oil from the Strategic Petroleum Reserve and put off new purchases for the stockpile.

"We're asking that this be done, and I don't think we have much choice," said Sen. Charles Schumer, D-New York. "The economy seems to be going along nicely now. But if you ask any economist what's the No. 1 thing that could stop it, it's oil prices."

Bush has rejected previous calls to ease price spikes by releasing oil from the reserve, which he says should be left intact for national emergencies.

But Schumer said tapping the oil reserve would be a money-making proposition for the government, since it would be releasing crude into the market when prices are high and could buy back those stockpiles when prices come down. And Sen. Barbara Boxer, D-California, said Bush's refusals amount to "a gift to the oil companies."

"Taxpayers are paying to fill the SPRO with the highest prices ever," she said. "That makes no sense while our consumers are facing this madness at the pump."

At least one Republican -- Sen. Susan Collins of Maine, whose state has a large number of heating oil consumers -- joined six Democratic senators in signing a letter to Bush.

The rising cost of crude oil drove gasoline prices up an average of 7 cents a gallon over the past two weeks to an average of $1.97 for a gallon of self-serve regular, according to the Lundberg Survey's nationwide canvass of filling stations.

In Los Angeles and San Francisco, prices at some gas station have topped $2.50 a gallon, Boxer said. And the U.S. summer vacation season -- which typically boosts demand for fuel -- has yet to begin.

Bush did not specifically address the rising cost of gasoline in his Columbus speech, but he noted that the United States now imports more than half its oil from abroad -- "and our dependence is growing."

Bush also called on Congress to back the development of "clean coal" technology, which would allow broader use of the most abundant U.S. energy source with less environmental damage; encourage the construction of new nuclear power plants; and overhaul aging electrical grids and pipeline networks.